Weekly Papers on Quantum Foundations (39)

Highlighting relations between Wave-particle duality, Uncertainty principle, Phase space and Microstates. (arXiv:2205.08538v2 [quant-ph] UPDATED) 

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physics.hist-ph updates on arXiv.org

 by 

Ravo Tokiniaina Ranaivoson, Voriraza Séraphin Hejesoa, Raoelina Andriambololona, Nirina Gilbert Rasolofoson, Hanitriarivo Rakotoson, Jacqueline Rabesahala Raoelina Andriambololona, Lala Rarivomanantsoa, Naivo Rabesiranana

Fri Sep 23 2022 08:50:01 (1 day)

# 1.

The wave-particle duality is often considered as the modern and satisfactory answer that man found in searching to know the nature of light after more than 2000 years of questioning. It is also the answer given by quantum physics concerning the nature of matter particles and any other radiations. The aim of this work is to perform an analysis of this concept of wave-particle duality from a historical, philosophical and scientific point of view and to study and discuss about the relations which exist between it, the uncertainty principle and the concepts of phase space and microstates considered in statistical mechanics. These relations will be described and analyzed both from a physico-mathematical and historico-philosophical perspective. It is, in particular, highlighted that while the concepts of phase space and microstates were already introduced in classical physics long before the discovery of the wave-particle duality, a correct understanding of them cannot be achieved without quantum physics. But conversely, it is also shown that the relations of the wave-particle duality with uncertainty principle, phase space and microstates that are highlighted can help in a deeper understanding and more adequate description of this duality.

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Matter and forces near physical black holes. (arXiv:2209.10766v1 [gr-qc]) 

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gr-qc updates on arXiv.org

 by 

Pravin Kumar Dahal, Ioannis Soranidis, Daniel R. Terno

Fri Sep 23 2022 08:49:59 (1 day)

# 2.

We describe the general features of formation and disappearance of regular spherically-symmetric black holes in semiclassical gravity. The allowed models are critically dependent on the requirement that the resulting object evolves in finite time according to a distant observer. Violation of the null energy condition is mandatory for this to happen, and we study the properties of the necessary energy-momentum tensor in the vicinity of the apparent horizon. In studies of the kinematics of massive test particles, it is found that the escape from a black hole is possible only on the ingoing trajectories when the particles are overtaken by the contracting outer apparent horizon. Tidal forces experienced by geodesic observers, infalling or escaping, are shown to be finite at the apparent horizon, although this is not true for non-geodesic trajectories.

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Towards testing the Fr\”ohlich-Morchio-Strocchi mechanism in quantum gravity. (arXiv:2209.10961v1 [hep-th]) 

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gr-qc updates on arXiv.org

 by 

Axel Maas

Fri Sep 23 2022 08:49:53 (1 day)

# 3.

Physics in (canonical) quantum gravity needs to be manifestly diffeomorphism-invariant. Consequently, physical observables need to be formulated in terms of manifestly diffeomorphism-invariant operators, which are necessarily composite. This makes an evaluation in general involved, even if the concrete implementation of quantum gravity should be treatable (semi-)perturbatively in general. A mechanism developed by Fr\”ohlich, Morchio and Strocchi for flat-space-time quantum field theory may also be applicable in this case. It may be possible to test this mechanism with methods like dynamical triangulation.

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Light in the darkness 

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Nature Physics

 by 

Alessandra Toncelli

Thu Sep 22 2022 08:00:00 (2 days)

# 4.

Nature Physics, Published online: 22 September 2022; doi:10.1038/s41567-022-01756-z

Laser light is usually limited to the same wavelength range as the spontaneous emission of the active material. A judicious choice of dielectric coatings on the cavity has now enabled laser emission far beyond the spectral range of the gain medium.

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(Competing?) Formulations of Newtonian Gravitation: Reflections at the Intersection of Interpretation, Methodology, and Equivalence 

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PhilSci-Archive: No conditions. Results ordered -Date Deposited.

Thu Sep 22 2022 06:53:53 (2 days)

# 5.

Coffey, Kevin (2022) (Competing?) Formulations of Newtonian Gravitation: Reflections at the Intersection of Interpretation, Methodology, and Equivalence. [Preprint]

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When “Replicability” is More than Just “Reliability”: The Hubble Constant Controversy 

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PhilSci-Archive: No conditions. Results ordered -Date Deposited.

Thu Sep 22 2022 05:23:51 (2 days)

# 6.

McCoy, C.D. and Matarese, Vera (2022) When “Replicability” is More than Just “Reliability”: The Hubble Constant Controversy. [Preprint]

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On Selleri’s “Weak Relativity”. (arXiv:2209.09551v1 [gr-qc]) 

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physics.hist-ph updates on arXiv.org

 by 

Marco Mamone-Capria

Wed Sep 21 2022 09:13:14 (3 days)

# 7.

F. Selleri’s main arguments for the restoration of absolute simultaneity in physics are analysed and shown to be faulty. In particular both the classical Sagnac effect and the recent so-called linear Sagnac effect can be dealt with within special relativity in a natural way. The appeal to the conventionality of simultaneity thesis is also shown to be ineffectual. Other arguments, such as the two spaceships’ argument and the block universe argument are briefly examined. Notwithstanding a negative overall assessment, the importance of keeping alive the research on the foundations of relativity is emphasized and Selleri’s role in this undertaking appreciated.

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Maxwell’s demon and impossibility statements: Einstein on perpetuum mobile of the second kind. (arXiv:2209.00504v2 [physics.hist-ph] UPDATED) 

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physics.hist-ph updates on arXiv.org

 by 

Galina Weinstein

Wed Sep 21 2022 09:13:13 (3 days)

# 8.

This paper discusses Maxwell’s demon thought experiment. In recent years, there has been extensive research on Maxwell’s demon. I first provide a detailed overview of important historical milestones of Maxwell’s demon thought experiment. Einstein would often write about both relativity and thermodynamics. In this paper, I first argue that: 1. Einstein spoke of Perpetuum mobile of the second kind (a Maxwell’s demon) in the context of the discovery of his relativity theory, the famous chasing a light beam thought experiment, and the contraction of lengths. 2. He would often compare relativity with thermodynamics. 3. When doing so, he would say that perpetual motion machines cannot exist. In the same category, no signal transmission faster than light is possible. 4. Einstein’s approach in speaking of the principles of thermodynamics and relativity suggests that he was occupied with “impossibility statements”. After discussing the essential aspects of Maxwell’s demon and the different ways of excorcising the demon, I examine the role of “impossibility statements” in Maxwell’s demon thought experiment.

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A “thoughtful” Local Friendliness no-go theorem: a prospective experiment with new assumptions to suit. (arXiv:2209.08491v1 [quant-ph]) 

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physics.hist-ph updates on arXiv.org

 by 

Howard M. Wiseman, Eric G. Cavalcanti, Eleanor G. Rieffel

Tue Sep 20 2022 09:16:11 (4 days)

# 9.

A recent paper by two of us and co-workers, based on an extended Wigner’s friend scenario, demonstrated that certain empirical correlations predicted by quantum theory (QT) violate inequalities derived from a set of metaphysical assumptions we called “Local Friendliness” (LF). These assumptions are strictly weaker than those used for deriving Bell inequalities. Crucial to the theorem was the premise that a quantum system with reversible evolution could be an observer (colloquially, a “friend”). However, that paper was noncommittal on what would constitute an observer for the purpose of an experiment. Here, we present a new LF no-go theorem which takes seriously the idea that a system’s having thoughts is a sufficient condition for it to be an observer. Our new derivation of the LF inequalities uses four metaphysical assumptions, three of which are thought-related, including one that is explicitly called “Friendliness”. These four assumptions, in conjunction, imply LF for the type of friend that Friendliness commits one to accepting as an observer. In addition to these four metaphysical assumptions, this new no-go theorem requires two assumptions about what is technologically feasible: Human-Level Artificial Intelligence, and Universal Quantum Computing which is fast and large scale. The latter is often motivated by the belief that QT is universal, but this is not an assumption of the theorem. The intent of the new theorem is to give a clear goal for future experimentalists, and a clear motivation for trying to achieve that goal, by using carefully chosen and widely held assumptions. The popular stance that “quantum theory needs no interpretation” does not question any of our assumptions and so is ruled out by the theorem. Finally, we quantitatively discuss how difficult the experiment we envisage would be, and briefly discuss milestones on the paths towards it.

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Coherent simulation with thousands of qubits 

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Nature Physics

 by 

David Bernal Neira

Tue Sep 20 2022 08:00:00 (4 days)

# 10.

Nature Physics, Published online: 20 September 2022; doi:10.1038/s41567-022-01772-z

Using a quantum annealer to simulate the dynamics of phase transitions shows that superconducting quantum devices can coherently evolve systems of thousands of individual elements. This is an important step toward quantum simulation and optimization.

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On Progress in Metaphysics 

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PhilSci-Archive: No conditions. Results ordered -Date Deposited.

Tue Sep 20 2022 05:57:04 (4 days)

# 11.

Salimkhani, Kian and Rolffs, Matthias (2022) On Progress in Metaphysics. [Preprint]

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Lotteries, Bookmaking and Ancient Randomizers: Local and Global Analyses of Chance 

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PhilSci-Archive: No conditions. Results ordered -Date Deposited.

Tue Sep 20 2022 05:55:27 (4 days)

# 12.

Norton, John D. (2022) Lotteries, Bookmaking and Ancient Randomizers: Local and Global Analyses of Chance. [Preprint]

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Wave Packet Dynamics in Synthetic Non-Abelian Gauge Fields 

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PRL: General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

 by 

Mehedi Hasan, Chetan Sriram Madasu, Ketan D. Rathod, Chang Chi Kwong, Christian Miniatura, Frédéric Chevy, and David Wilkowski

Mon Sep 19 2022 18:00:00 (4 days)

# 13.

Author(s): Mehedi Hasan, Chetan Sriram Madasu, Ketan D. Rathod, Chang Chi Kwong, Christian Miniatura, Frédéric Chevy, and David Wilkowski

Researchers produce analogues of hard-to-study quantum phenomena in a gas of strontium atoms near absolute zero.

http://cdn.journals.aps.org/journals/PRL/key_images/10.1103/PhysRevLett.129.130402.png

[Phys. Rev. Lett. 129, 130402] Published Mon Sep 19, 2022

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Efficient Contextual Ontological Model of $n$-Qubit Stabilizer Quantum Mechanics 

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PRL: General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

 by 

Christoffer Hindlycke and Jan-Åke Larsson

Mon Sep 19 2022 18:00:00 (4 days)

# 14.

Author(s): Christoffer Hindlycke and Jan-Åke Larsson

The most well-known tool for studying contextuality in quantum computation is the n-qubit Stabilizer state tableau representation. We provide an extension that not only describes the quantum state but is also outcome deterministic. The extension enables a value assignment to exponentially many Pauli…

[Phys. Rev. Lett. 129, 130401] Published Mon Sep 19, 2022

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Review of Slobodan Perović‘s From Data to Quanta — Niels Bohr’s Vision of Physics 

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PhilSci-Archive: No conditions. Results ordered -Date Deposited.

Mon Sep 19 2022 07:43:26 (5 days)

# 15.

Cuffaro, Michael E. (2022) Review of Slobodan Perović’s From Data to Quanta — Niels Bohr’s Vision of Physics. [Preprint]

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Born rule from counting states 

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PhilSci-Archive: No conditions. Results ordered -Date Deposited.

Mon Sep 19 2022 07:42:33 (5 days)

# 16.

Stoica, Ovidiu Cristinel (2022) Born rule from counting states. [Preprint]

arXiv:2209.05549 (quant-ph)[Submitted on 12 Sep 2022]

Quantum Physics from Number Theory

Tim Palmer

The properties which give quantum mechanics its unique character – unitarity, complementarity, non-commutativity, uncertainty, nonlocality – derive from the algebraic structure of Hermitian operators acting on the wavefunction in complex Hilbert space. Because of this, the wavefunction cannot be shown to describe an ensemble of deterministic states where uncertainty simply reflects a lack of knowledge about which ensemble member describes reality. This has led to endless debates about the ontology of quantum mechanics. Here we derive these same quantum properties from number theoretic attributes of trigonometric functions applied to an explicitly ensemble-based representation of discretised complex Hilbert states. To avoid fine-tuning, the metric on state space must be p-adic rather than Euclidean where 1/p determines the fineness of the discretisation. This hints at both the existence of an underpinning fractal state-space geometry onto which states of the world are constrained. In this model, violation of Bell inequalities is a manifestation of this geometric constraint and does not imply a breakdown of local space-time causality. Because the discretised wavefunction describes an ensemble of states, there is no collapse of the wavefunction. Instead measurement describes a nonlinear clustering of state-space trajectories on the state-space geometry. In this model, systems with mass greater than the Planck mass will not exhibit quantum properties and instead behave classically. The geometric constraint suggests that the exponential increase in the size of state space with qubit number may break down with qubit numbers as small as a few hundred. Quantum mechanics is itself a singular limit of this number-theoretic model at p=∞. A modification of general relativity, consistent with this discretised model of quantum physics, is proposed.

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